Comparison and Properties of 3D Printing Filaments
Introduction
There are countless filaments made from different materials with various fillers on the market. Hopefully, we can answer the following question: What filament should I use? After reading this article, the reader should have an understanding of the most common materials available on the market.
Easy-to-Print Filaments
Easy-to-print filaments can be printed with almost any 3D printer and are relatively forgiving of incorrect settings.
PLA (Polylactide)
PLA is the most common 3D printing material for consumers, and for good reason. It is easy to print, has a low printing temperature, and barely lifts from the print bed. Although a heated bed is not mandatory, it improves print quality. Another advantage of PLA is its low odor during printing; some users describe it as smelling of sweet, candy-like fumes, depending on the type of filament.
PLA is available in almost all colors, and special filaments such as conductive, glow-in-the-dark, and wood or metal composites are also available. As a material, PLA is biodegradable and more environmentally friendly than most other filaments, and it is made from renewable resources such as corn starch or sugarcane.
While PLA is an easy and versatile material, it is brittle and not suitable for objects that are subjected to high stress, bending, or repeated drops. Additionally, PLA begins to soften at around 60 °C, so it cannot be used in applications where temperatures rise high. PLA can even begin to soften in a car on a hot summer day. Common print objects include models, low-wear toys, prototypes, and containers.
Sunlu PLA technical properties
PETG (Polyethylene terephthalate, glycol-modified)
PETG is a strong, flexible, and easy-to-print material. Its properties lie between PLA and ABS: more flexible and durable than PLA, but easier to print than ABS. PETG is hygroscopic, so it should be stored in a dry place. Typically, undried PETG causes thin strands, known as stringing, to form in the print.
PETG is suitable for functional parts, mechanical components, and protective casings. The surface may scratch more easily than ABS, but overall, it is a versatile and durable filament.
Properties:
- Strength: High
- Flexibility: Medium
- Durability: High
- Print temperature: 220–250 °C
- Print bed temperature: 50–75 °C
- Shrinkage/warping: Minimal
Sunlu PETG technical properties
Intermediate Filaments
Intermediate filaments are more challenging to print than easy-to-print filaments. However, they can be printed successfully with certain limitations and correct settings on most modern printers.
ABS (Acrylonitrile Butadiene Styrene)
ABS is the second most popular filament after PLA, known for its durability and heat resistance. It is used in many consumer products, such as LEGO bricks and bicycle helmets. ABS requires slightly more demanding printing conditions: higher temperatures and an enclosed chamber. Printing should be done in a well-ventilated area and an enclosed chamber due to harmful fumes. Large and narrow ABS parts practically require a heated chamber to prevent warping; small ABS parts can be printed without a heated chamber.
ABS is well-suited for mechanical parts and objects that need to withstand rough handling and higher temperatures. It is also moderately flexible and can be post-processed with acetone to achieve a glossy finish.
Sunlu ABS Technical Properties
ASA (Acrylonitrile Styrene Acrylate)
ASA was developed as an alternative to ABS, specifically for outdoor use. It is strong, rigid, and relatively easy to print. The biggest advantage of ASA is its excellent resistance to UV, weather, and chemicals. Unlike ABS, ASA does not yellow or degrade outdoors in sunlight, making it ideal for outdoor furniture, birdhouses, and garden accessories.
When printing, proper ventilation and cooling should be considered, as excessive cooling of the print will cause warping and poor layer adhesion. ASA printing has the same prerequisites as ABS.
If I had to choose only one filament to use, ASA would be the winner. ASA offers a good balance between strength and flexibility, making it a versatile filament for prototypes and finished parts.
Properties:
- Strength: High
- Flexibility: Medium
- Durability: High, especially UV and chemical resistance
- Print temperature: 240–280 °C
- Print bed temperature: 90–110 °C
- Shrinkage/warping: Moderate
- Applications: Outdoor use, protective housings, automotive parts
Eryone ASA technical properties
TPU / TPE
TPU (thermoplastic polyurethane) and other TPE-family filaments are extremely flexible and durable. They withstand twisting, compression, and wear, making them suitable for items such as phone cases, toys, and clothing. TPU is slightly stiffer than TPE, making it easier to print and retaining its flexibility better in cold conditions. The hardness of flexible filaments is measured by the Shore A scale; the lower the number, the more flexible and challenging the filament is to print. The most common TPU filaments have a hardness of 95A-85A. Printing 95A is still pleasant, 85A is manageable, and anything below that will cause significant headaches.
The challenge of printing TPU comes from the material's flexibility; if printed too quickly or with too high a retraction setting, the TPU will either get stuck between the extruder gears or narrow to the point where the extruder gears cannot bite into the filament. When printing TPU, it is typical to use a slower speed, and a direct drive extruder is better than a Bowden-style one.
TPU and TPE filaments are suitable for prints that need to withstand a lot of physical stress, bending, and hard impacts. TPU filaments are the perfect material for 3D-printed seals.
Properties:
- Strength: Medium
- Flexibility: Very high
- Durability: Very high
- Print temperature: 210–230 °C
- Print bed temperature: 30–60 °C (not mandatory)
Technical Filaments
Printing technical filaments requires considerable expertise, higher equipment requirements such as heated chambers or special print beds. However, these filaments also offer extremely useful properties, such as high temperature resistance, chemical resistance, and other properties required, for example, in designing parts for a car engine compartment.
Polypropylene (PP)
Polypropylene (PP) is a lightweight, flexible, and chemically highly resistant filament. It is also food-safe, which makes it an attractive material for storage and packaging applications. The challenge of PP in 3D printing is its tendency to warp and the fact that PP adheres to virtually nothing but itself, which makes it very challenging for prints to stick to the bed unless a special PP-designed bed is used.
PP is excellent for parts that require lightness and chemical resistance, such as technical components and packaging. PP is also suitable for hinges where the material bends continuously.
Properties:
- Strength: High
- Flexibility: Medium–High
- Durability: High
- Print temperature: 220–250 °C
- Print bed temperature: 80–100 °C
- Applications: Food-safe packaging, lightweight technical parts
Polycarbonate (PC)
PC is an extremely strong and heat-resistant filament, suitable for mechanical parts, automotive components, and applications requiring optical transparency. It is also hygroscopic and requires higher print temperatures and a heated bed. PC is slightly more flexible than acrylic but less flexible than Nylon.
Many so-called PC filaments are blends because pure PC requires chamber temperatures of up to 120°C to achieve good prints. When printing at lower temperatures, internal stresses remain in the PC, which weakens its impact resistance. Post-processing in an oven removes these stresses and achieves the true properties of the material.
Properties:
- Strength: Very high
- Flexibility: Medium
- Durability: Very high
- Print temperature: 270–310 °C
- Print bed temperature: 90–110 °C
Nylon (PA)
Nylon, or Polyamide, is one of the most popular industrial plastics. Its combination of flexibility, strength, durability, and low friction coefficient has led to nylon's popularity. There are generally two types of nylon filament available, PA6 and PA12. The difference between them is that PA6 is slightly stiffer and tougher, while PA12 offers better chemical and moisture resistance, as well as a lower shrinkage percentage, making it easier to print large parts. Typically, nylon is used in industry for gears, bearings, and fasteners. At the hobby level, nylon is a popular material for parts under a car hood, motorcycle fairings, and various mechanically stressed components.
Printing nylon is somewhat challenging due to its poor adhesion to the print bed and its tendency to warp if printing settings are not optimal. When printing PA, it is advisable to have a heated chamber and some adhesive on the print bed.
Properties
- Strength: High
- Flexibility: High
- Durability: High
- Print temperature: 240–260 °C
- Print bed temperature: 70–100 °C
- Shrinkage/warping: Moderate
- Applications: Mechanical parts, prototypes, hinges, gears, sports equipment
Sunlu PA6 mechanical properties
PPS (Polyphenylene Sulfide)
PPS is a high-performance filament primarily used in industrial applications. It offers excellent resistance to high temperatures, chemicals, and UV radiation. PPS is almost non-porous and self-lubricating, making it an excellent material for durable, wear- and chemical-resistant parts.
Printing PPS filament requires exceptionally high nozzle and bed temperatures, as well as a heated chamber. PPS can be printed either directly at the correct chamber temperature of 120°C+ or at approximately 60°C, in which case achieving full mechanical and heat resistance properties requires post-heat treatment in an oven.
PPS is used in electrical components, automotive parts, and chemical tanks, where other filaments would not withstand the conditions.
Properties:
- Strength: Very High
- Flexibility: Low–Medium
- Durability: Very high, chemical and heat resistance
- Print temperature: 280–350 °C
- Print bed temperature: 100–140 °C
- Applications: Industrial use, chemical tanks, heat-resistant parts
Fillers
Fibers are often added to filaments in powdered form to strengthen the filament, reduce warping of the print, and improve surface quality. There are also filaments that have been filled with substances purely for visual reasons; these filaments are slightly inferior in properties compared to the raw version.
Carbon Fiber
Carbon fiber-reinforced filaments (PLA, PETG, Nylon) are extremely stiff, lightweight, and durable. They are suitable for structural and mechanical parts where strength and precise shape are required. They wear down nozzles and require a hardened or coated nozzle.
Fiberglass
Fiberglass has properties almost equivalent to carbon fiber. The main difference between these two fibers is the slight electrical conductivity of carbon fiber and the better availability of fiberglass-filled filaments in multiple colors.
Wood
Wood-PLA is PLA mixed with wood fibers, giving prints a natural wood-like appearance. It is especially suitable for decorative items and models where aesthetics are more important than mechanical properties. Wood filament wears nozzles more and requires precision in print temperature.
Metal
Metal filament is a mixture of PLA or ABS and metal powder, giving prints the look and feel of real metal objects. However, filaments filled with metal powder do not achieve the other properties of metal beyond weight. Metal-filled filaments wear out nozzles more and are suitable for aesthetic and lightly functional items.
Glow in the dark
Glow-in-the-dark filaments have glow-in-the-dark powder mixed into the base polymer to achieve the glow effect. Glow-in-the-dark filaments wear out nozzles and require a nozzle made of hardened steel.